Having trouble with normal calls

[Briony101]

I'm having trouble with normal calls the people on the other end can't hear me but they can if it's over Whatsapp or messenger and I'm unsure if it's my phone or my sim please help

[bristolian]

Are you using VoLTE/4G-calling or WiFi-calling when you have this problem?

Has this only started recently? Does it only happen in one specific location or multiple?